body {
    font-family: Arial, sans-serif;
}
.container {
    width: 100%;
    max-width: 600px; /* 增大容器宽度 */
    margin: 50px auto;
    padding: 30px;
}
.card {
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 20px;
}
.card-header {
    font-size: 1.4rem;
    font-weight: bold;
    text-align: center;
    margin-bottom: 20px;
}
.alert {
    padding: 12px;
    margin-bottom: 15px;
    border-radius: 5px;
    background-color: #f8d7da;
    color: #721c24;
}
.form-group {
    margin-bottom: 20px;
}
.error {
    color: red;
    font-size: 0.875rem;
}
.info {
    font-size: 0.85rem;
    color: #666;
}
.btn {
    display: block;
    width: 100%;
    padding: 12px;
    text-align: center;
    background-color: #333;
    color: white;
    border: none;
    cursor: pointer;
    margin-top: 15px;
    border-radius: 5px;
    font-size: 1rem;
}
.btn.cancel {
    background-color: #bbb;
    color: black;
}